Daily ingestion of alginate reduces energy intake in free-living subjects

Sodium alginate is a seaweed-derived fibre that has previously been shown to moderate appetite in models of acute feeding. The mechanisms underlying this effect may include slowed gastric clearance and attenuated uptake from the small intestine. In order to assess whether alginate could be effective as a means of appetite control in free-living adults, 68 males and females (BMI range: 18.50-32.81 kgl M-2) completed this randomised, controlled two-way crossover intervention to compare the effects of 7 day daily ingestion of a strong-gelling sodium alginate formulation against a control. A sodium alginate with a high-guluronate content was chosen because, upon ingestion, it forms a strong gel in the presence of calcium ions. Daily preprandial ingestion of the sodium alginate formulation produced a significant 134.8 kcal (7%) reduction in mean daily energy intake. This reduced energy intake was underwritten by significant reductions in mean daily carbohydrate, sugar, fat, saturated fat and protein intakes. The absence of any significant interaction effects between the main effect of preload type and those of gender, BMI classification and/or timing of preload delivery indicates the efficacy of this treatment for individuals in different settings. These findings suggest a possible role for a strong-gelling sodium alginate formulation in the future management of overweight and obesity. (C) 2008 Elsevier Ltd. All rights reserved

Inter-Grade and Inter-Batch Variability of Pharmaceutical-Grade Sodium Alginate

Polymeric excipients are generally the least well-characterized components of pharmaceutical formulations. The aim of this dissertation work is to facilitate the quality-by-design (QbD) approach to pharmaceutical formulation and manufacturing by evaluating the inter-grade and inter-batch variability of pharmaceutical-grade polymeric excipients. Sodium alginate, a widely used polymeric excipient, was selected for evaluation using appropriate analytical methods and test conditions, especially rheological methods. The materials used were six different grades of sodium alginate and an additional ten batches of one of the grades. To compare the six grades, steady shear measurements were conducted on solutions at 1, 2, and 3% w/w, consistent with their use as thickening or binding agents. Small amplitude oscillation (SAO) measurements were conducted on sodium alginate solutions at higher concentrations (4-13% w/w) corresponding to their use in controlled release matrices. In order to compare the ten batches of one grade, steady shear and SAO measurements were performed on their solutions at 2% w/w and 8% w/w, respectively. Results show that rheological properties of sodium alginate solutions are influenced by both molecular weight and chemical composition of sodium alginate. ¡§One-point¡¨ apparent viscosity data obtained at one low concentration and one shear rate is not representative of the complex rheological behavior of various grades of sodium alginate solutions at higher concentrations or other shear rates. The potential interchangeability of these different grades used as thickening or binding agents could be established by comparing the apparent viscosities of their solutions as a function of both alginate concentration and shear conditions. For sodium alginate used in controlled release formulations, both steady shear (at one low concentration, e.g., 2% w/w) and SAO measurements (at one high concentration indicative of polymer gel state, e.g., 8% w/w) are recommended to be performed on sodium alginate solutions to ensure interchangeability. Furthermore, among batches of the same grade, significant differences in rheological properties were observed, especially at the high solution concentration (i.e., 8% w/w). In summary, inter-grade and inter-batch variability of sodium alginate can be determined using steady shear and SAO methods. The influence of inter-grade and inter-batch variability of sodium alginate on the functionality of sodium alginate used in matrix tablets was investigated with a focus on compression properties, swelling, erosion behavior of alginate matrix tablets, and drug release from matrix tablets. The compression behavior of four grades and three batches of sodium alginate were studied by compaction energetics, out-of-die Gurnham, and out-of-die Heckel analysis. It was found that sodium alginates deform less plastically than microcrystalline cellulose (MCC PH102) but similar to lactose anhydrous. Sodium alginates also demonstrate more elastic deformations during compression than both MCC PH102 and lactose anhydrous. Compacts prepared from multiple batches of the same grade varied in porosity. The same tensile strength of compacts can be achieved by compressing the multiple batches to the same porosity. Sodium alginate tablets undergo both swelling and erosion in water. Grades with substantially higher apparent viscosities at low solution concentration exhibit a higher percentage of water uptake and a low percentage of erosion. Those batches not significantly different in their apparent viscosities at low solution concentration but significantly different in viscoelasticity at high solution concentrations do demonstrate significant differences in their swelling and erosion behavior. Acetaminophen release from sodium alginate matrix tablets prepared from the four grades and three batches can be well described by a zero-order equation. Significant differences in release profile were observed among various grades and batches. In conclusion, the inter-grade and inter-batch variability of sodium alginate has a significant influence on the swelling, erosion, and drug release behavior of sodium alginate matrix tablets. Apparent viscosities of sodium alginate solution at low concentration alone are not sufficient to predict the functionality of sodium alginate used in matrix tablets. Viscoelastic properties of sodium alginate solutions at high concentrations indicative of polymer gel state are appropriate to be characterized. Further study was conducted to determine whether sodium alginate solutions\u27 rheological parameters are relevant to sodium alginate\u27s use in the formulation of calcium alginate gels. Among the grades with similar guluronic acid percentage (%G), there is a significant correlation between gel fracture force and apparent viscosity. However, the results for the partial correlation analysis for all six grades of sodium alginate show that gel fracture force is significantly correlated with %G, but not with the rheological properties of the sodium alginate solutions. Studies of the ten batches of one grade of sodium alginate show that apparent viscosities of their solutions do not correlate with gel fracture force while tan δ values are significantly, but minimally, correlated to gel fracture force. Inter-batch differences in the rheological behavior for one specific grade of sodium alginate are insufficient to predict the corresponding calcium alginate gel\u27s mechanical properties. In summary, rheological methods, including steady shear and small amplitude oscillation, are able to identify the inter-grade and inter-batch variability of sodium alginate. Inter-grade and inter-batch variability of sodium alginate could lead to substantial differences in the functionality of sodium alginate in matrix tablets and in calcium alginate gels. Rheological properties of sodium alginate in solution are suggestive of its functionality as thickeners, or as controlled release agent. However, rheological properties of sodium alginate in solution do not seem to be sufficient to predict the mechanical properties of the corresponding calcium alginate gels

The effect of nanocoatings enriched with essential oils on ‘Rocha’ pear long storage

The effect of coating 'Rocha' pears with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) or citral (Cit) was investigated. Fruit were treated with the nanoemulsions: sodium alginate 2% (w/w) + citral 1% (w/w) (Cit1%); sodium alginate 2% (w/w) + citral 2% (w/w) (Cit2%); sodium alginate 2% (w/w) + lemongrass 1.25% (w/w) (LG1.25%); sodium alginate 2% (w/w) + lemongrass 2.5% (w/w) (LG2.5%). Then, fruit were stored at 0 °C and at 95% relative humidity, for six months. Fruit samples were taken after two, four and six months, and then placed at 22 °C. Upon removal and after 7 d shelf-life, fruit were evaluated for colour CIE (L*, h◦), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage, microbial growth, symptoms of superficial scald and internal browning. All nanoemulsions had droplets in the nano range <500 nm, showed uniformity of particle size and stable dispersion. Cit-nanoemulsions had lower droplet size and higher stability than LG. No nanoemulsion showed cytotoxicity. Coatings reduced fruit colour evolution and preserved better firmness than control. After shelf-life, better firmness was found in LG-coated fruit. Coatings did not affect SSC and TA. Microbial growth was below the safety limits in all treatments. Fruit treated with LG-nanoemulsions did not show scald symptoms and panelists preferred LG1.25% coated fruit. Cit2% treated fruit showed the highest scald and internal browning symptoms, while LG1.25% did not show any disorders. This study suggests that LG-nanocoatings have the potential for preserving the quality of 'Rocha' pear.FCT (SFRH/BPD/108831/2015); UID/BIA/04325/2019/ UID/Multi/00631/2019/ UID/AMB/50017/2019info:eu-repo/semantics/publishedVersio

Aktivitas Antibakteri Bahan Cetak Berbasis Ekstrak Natrium Alginat dari Alga Merah (Kappaphycus alverezii) terhadap Lactobacillus acidophilus

Alginate impression material is a material that is often used for impression tissue in the oral cavity, and can be one of the agents of infection transmission in dental practice. Microorganisms can adhere to the mold such as Lactobacillus acidophilus bacteria. L. acidophilus were isolated from active caries and were considered as secondary invaders in the dental caries invasion process. The development of impression materials that have antibacterial capabilities needs to be done, one of which is by using materials derived from red algae (Kappaphycus alverezii). This plant contains a lot of alginate which is the main components of the cell wall, consisting of calcium, magnesium, sodium and potassium alginate salts. Synthesizing sodium alginate from red algae and analyzing the antibacterial activity of sodium alginate-based impression materials from red algae against L. acidophilus. Extraction of alginate from red algae using the acid method and conversion of alginic acid to sodium alginate by adding NaOH. The impression material is made with the addition of sodium alginate. Antibacterial activity test by well diffusion method. This study consisted of 3 groups, namely control (K), red algae sodium alginate extract (P1), and impression material with red algae sodium alginate extract (P2). Groups K, P1 and P2 had an average inhibition zone of 0 mm, 15.56 mm, 17.22 mm, respectively. Kruskal Wallis and Mann Whitney test showed significant differences between groups. Impression material based on sodium alginate extract from red algae has strong antibacterial activity against L. acidophilus

A note on the effect of calcium alginate coating on quality of refrigerated strawberries.

peer-reviewedAn alginate-based edible coating was investigated for the preservation of the quality of strawberries during cold storage (5 °C). Strawberries were immersed, successively, in sodium alginate and calcium chloride solutions to generate a surface coating of calcium alginate. The quality of coated and non-coated strawberries was evaluated by weight loss, visible decay, titratable acidity, total soluble solids and reducing sugar concentration over a 14-day storage period. Results showed that coating with calcium alginate had no significant effects on weight loss or physicochemical parameters when compared to control fruit, but it did result in the postponement of visible decay during refrigerated storage

Encapsulation of Bifidobacterium longum in alginate-dairy matrices and survival in simulated gastrointestinal conditions, refrigeration, cow milk and goat milk

The aim of this study was to microencapsulate Bifidobacterium longum subsp. infantis CCUG 52486 using the extrusion method in a variety of matrices, namely sodium alginate (SA), sodium alginate-cow milk (SACM), sodium alginate-goat milk (SAGM) and sodium alginate-casein hydrolysate (SACH), and to evaluate the survival of free and encapsulated bacterial cells under different conditions. The encapsulation yield, size and surface morphology of the microcapsules were evaluated. The survival of microencapsulated bacterial cells and free bacterial cells were evaluated under simulated gastrointestinal conditions as well as in refrigeration, cow milk and goat milk during storage at 4 oC for 28 days. The average size of SACM capsules and SAGM capsules was 2.8±0.3 mm and 3.1±0.2 mm respectively. Goat milk and cow milk based matrices resulted in dense microcapsules which led to better performances in simulated gastrointestinal conditions than SA and SACH microcapsules. The bacterial cells encapsulated in SAGM showed the highest survival rate in cow milk (7.61 log cfu g-1) and goat milk (8.10 log cfu g-1) after the storage of 28 d. The cells encapsulated in SA and SACH and the free cells performed poorly under the simulated gastrointestinal conditions and in all different storage conditions. This study showed that SACM and SAGM are suitable to encapsulate B. longum subsp. infantis CCUG 52486 using the extrusion technique and more specifically, SAGM has a potential to be used as a new encapsulation material for encapsulating probiotic bacteria, resulting milk and goat milk-based products with higher probiotic cell concentrations during refrigerated storage

Improvement of Heat Stability of Paper Made From Sulfite and Kraft Pulps

Paper made from bleached sulphite and sulphate pulps and then treated with sodium alginate and antimony resin solutions show far less physical and chemical degradation with heat than these same papers when not treated with these solutions. Sodium alginate and antimony resins solutions appear to inhibit degradation up to 175C for 45 minutes but are not effective when the papers are heated to 210 C for 45 minutes. The paper made with bleached sulphate pulp and saturated with sodium alginate solution showed an appreciable increase in folding strength when heated at 175C for 45 minutes, which is most unusual. The presence of iron which might come from process water appears to negate the effect of alginate and antimony solutions and should be held to a minimum when making paper meant for unusual heat resistance. Aquapel-kymene 557 sizing solution either inhibits chemical degradation as measured by the copper number test or else interferes with the test by blocking the reducing groups which are generally regarded as products of degredation. Upon heating the Aquapel-kymene 557 complex must break down and aid in degradation of the sample as shown by the copper number. The permanence of paper might be enhanced if treated by the methods prescribed in this report. The utility of papers used for winding electric wires, for paper plates and for use on Virkotype presses might be improved with these treatments

Development of alginate beads for probiotic encapsulation: influence of different parameters in the beads size

In the present study different parameters were evaluated in the formation of alginate beads by ionotropic gelation (external extrusion). The size of alginate beads was determined and results showed that needle-CaCl2 solution distance, flow rate, sodium alginate concentration, needle diameter and molecular weight of sodium alginate influenced alginate beads formation. Moreover, was concluded that needle diameter was the parameter that most influenced the beads mean size

Effects of edible film of sodium alginate on quality changes of dressed kilka in frozen storage

The likely effects of sodium alginate edible coating on the quality of dressed kilka fish in the frozen storage was investigated. Sodium alginate edible coating was prepared in four concentrations (0.25, 0.75, 1.25, and 1.75%). Then, dressed kilka fish were coated with sodium alginate for 1h, packed in polyethylene dishes with cellophane blanket and stored at - 18°C. The amount of hem Iron, pH, percent lipid and organoleptic characteristics (odor, color) were assessed within 0, 1, 2, 3 and 4 months (sample size: 125 packs of 250g). Results showed a significant difference between the mean hem iron and percent lipid and increase in sodium alginate concentration (P0.05) with different levels of coating. Organoleptic results showed that the mean color and odor value of the samples were affected significantly by different levels of coating (P<0.05). Use of sodium alginate edible coating to protect hem iron and improve organoleptic properties can increase the quality of kilka in frozen storage up to 4 months

PREPARATION AND EVALUATION OF CHITOSAN SODIUM ALGINATE CARBAMAZEPINE MICROSPHERES

ABSTRACTObjective: The objective behind our study is that a mucoadhesive rectal hydrogel chitosan sodium alginate carbamazepine (CBZ) microspheres forthe purpose of controlled release for the treatment of epilepsy to avoid the possible side effects.Methods: The study was conducted to formulate controlled release chitosan sodium alginate CBZ microspheres with the dispersion of CBZ into thenatural polymers chitosan and sodium alginate forming microspheres conducting along with their evaluation studies.Results: The formulated microspheres were subjected to various evaluation parameters, and all the physical parameters examined are within theacceptable limits. Further, the optimized microsphere formulation (CM5) was characterized. Hence, the developed optimized microsphere formulation(CM5) seems to be a viable substitute to conventional drug delivery system for the effective management of epilepsy.Conclusion: The prepared formulation also provides a desired CBZ loaded sodium alginate microspheres with the controlled release drug delivery.Keywords: Carbamazepine, Sodium alginate microspheres, Particle size